He probably was good at first.
When Ronda's popularity exploded, he not only did not attempt to keep her grounded, he actually made all of that way worse than it ever should have been.
Combined with the fact that the dude is also highly emotional, which is the last thing Ronda needed. If she came off over emotional on TUF, he just fed those flames and did the same.
I think he did care about her but got completley swept up in the hype she generated.
So he may have helped her career early on but wound up helping to damage it irrerparably later on.
Ronda's mother def expressed great dissatisfaction with him during this period.